Sivaraman Dandapani

Fluorous Mitsunobu reagents and reactions

Abstract A fully fluorous Mitsunobu reaction procedure is introduced. This employs both existing [(C 6 F 13 CH 2 CH 2 C 6 H 4 ) 2 PPh] and new [C 8 F 17 CH 2 CH 2 C 6 H 4 PPh 2 ] fluorous phosphines and a new fluorous azodicarboxylate (C 6 F 13 CH 2 CH 2 OC(O)Nue5fbNCOOCH 2 CH 2 C 6 F 13 ). A procedure involving parallel reactions with representative nucleophiles and alcohols under typical Mitsunobu conditions in THF followed by rapid solid phase extraction (spe) over fluorous silica provides clean products in excellent yields. The fluorous fraction containing the oxidized phosphine oxide and the reduced hydrazide can be readily separated and the starting reagents can be regenerated by appropriate redox reactions in high yield for reuse.